Shallow-Marine Trace Fossils of the Pochico Formation, Southern Spain: Palaeoenvironmental and Palaeogeographic Implications at the Gondwanan and Peri-Gondwanan Realm

Journal of Iberian Geology 40 (3) 2014: 539-555 http://dx.doi.org/10.5209/rev_JIGE.2014.v40.n3.44308 www.ucm.es/info/estratig/journal.htm ISSN (print): 1698-6180. ISSN (online): 1886-7995

Lower/Middle Ordovician (Arenigian) shallow-marine trace fossils of the Pochico Formation, southern Spain: palaeoenvironmental and palaeogeographic implications at the Gondwanan and peri-Gondwanan realm

F.J. Rodríguez-Tovar1, M. Stachacz2, A. Uchman2, M. Reolid3

1Departamento de Estratigrafía y Paleontología, Facultad de Ciencias, Universidad de Granada, 18002 Granada, Spain 2Jagiellonian University, Institute of Geological Sciences, Oleandry Str. 2a, PL-30-063 Kraków, Poland 3Departamento de Geología, Universidad de Jaén, Campus Las Lagunillas sn, 23071 Jaén, Spain

e-mail addresses: [email protected] (F.J.R.-T., corresponding author); [email protected] (M.S.), [email protected] (A.U.); [email protected] (M.R.)

Received: 29 January 2014 / Accepted: 13 August 2014 / Available online: 30 October 2014

Abstract Nineteen ichnospecies belonging to thirteen ichnogenera (Archaeonassa, Catenichnus, Cochlichnus, Cruziana, Didymaulichnus, ?Di- plichnites, Gordia, Lingulichnus, Lockeia, cf. Monocraterion, Planolites, Ptychoplasma, and Rusophycus) occur in the Pochico Forma- tion (Arenigian) in the Aldeaquemada section, Sierra Morena, southern Spain, just above the Armorican Quartzite. They belong to the archetypal Cruziana ichnofacies, indicating a lower shoreface-upper offshore zone. The low degree of sediment reworking may be due to a high rate of sedimentation. The trace fossil assemblage, rich in large Cruziana, is typical of the Armorican Quartzite that developed on the margins of Gondwana and peri-Gondwanan microcontinents. The distribution of ichnofauna during the Early Ordovician was partly palaeogeographically controlled, although ichnological data from the literature point to paths of migration between Gondwana, Baltica and Laurentia. Differences between the ichnofauna of Gondwana and Baltica could be conditioned by facies (clastics in Gondwana and carbonates in Baltica) causing a taphonomic filter, because Cruziana requires diversified clastic deposits for preservation. The ichnofauna would also be influenced by trophic group amensalism between filter feeding and deposit feeding fauna, the former prevailing in Baltica and the latter in Gondwana. Keywords: Ichnofossils, Arenigian, clastic sediments, Gondwana, peri-Gondwana, Iberia

Resumen Se presenta el análisis sedimentológico/icnológico de los materiales de la Formación Pochico (Arenigian) de la sección de Aldeaque- mada, Sierra Morena, Sur de España, provincia de Jaén, justo por encima la Cuarcita Armoricana. Se han reconocido diecinueve icnoes- pecies pertenecientes a trece icnogéneros (Archaeonassa, Catenichnus, Cochlichnus, Cruziana, Didymaulichnus, ?Diplichnites, Gordia, Lingulichnus, Lockeia, cf. Monocraterion, Planolites, Ptychoplasma, y Rusophycus). Las características icnológicas junto con los rasgos sedimentológicos permiten asignarlas a las icnofacies arquetípicas de Cruziana, comunes de las zonas de shoreface inferior a offshore supe- rior. El grado de bioturbación relativamente bajo puede estar relacionado con una alta tasa de depósito. La asociación registrada, dominada por grandes Cruziana, es típica de la Cuarcita Armoricana desarrollada en los márgenes de Gondwana y peri-Gondwana. La distribucción de icnofósiles del Ordovícico temprano posee, en gran medida, un control paleogeográfico, aunque datos icnológicos procedentes de la literatura indican la existencia de migraciones entre Gondwana, Baltica y Laurentia. Las diferencias entre las asociaciones de Gondwana y Báltica pueden estar asociadas a las diferentes facies, con el dominio de materiales clásticos en Gondwana y de carbonatados en Báltica, causando un filtro tafonómico ya que el potencial de conservación de Cruziana es mucho mayor en las facies clásticas heterolíticas. A estos factores habría que añadir las estrategias de alimentación asociadas, diferenciando entre filtradores y aquellos que se alimentan de las partículas existentes en el sedimento, los primeros podrían verse favorecidos en Báltica y los segundos en Gondwana. Palabras clave: Icnofósiles, Arenigiense, sedimentos clásticos, Gondwana, peri-Gondwana, Iberia 540 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555

1. Introduction village by the El Negrillo pool of the Guarrizas River (GPS co-ordinates: N38°23.150′; W003°22.474′; ±9 m). Additional Arenigian shallow-marine clastic sediments of Western Eu- material was observed in the surroundings, especially at the rope, North Africa, South America and some parts of North bottom of the valley near this site, where nearly horizontal America are characterized by abundant trace fossils, includ- beds offered other in situ occurrences (GPS co-ordinates: ing large Cruziana, an ichnogenus first described from such N38°23.136′; W003°22.332′; ±8 m). Both localities are with- deposits in Bolivia (ďOrbigny, 1842). Trace fossils of these in the Despeñaperros Natural Park. facies are largely associated with quartzitic sandstones, in The Lower/Middle Ordovician in the Aldeaquemada France and on the Iberian Peninsula largely attributed to the area comprises two lithostratigraphic units: the Armorican Armorican Quartzite (Grès Armoricain) (Gutiérrez-Marco et Quartzite Formation and the Pochico Formation (Fig. 1C). al., 2002). The Armorican Quartzite, dated mostly to Areni- The Armorican Quartzite in the Central Iberian Zone is up gian, was deposited in several disconnected basins supplied to 500 m thick and composed of white orthoquartzites. The from local sources (Torsvik and Cocks, 2011). The Armorican lower part of the Armorican Quartzite Formation is not out- Quartzite and associated deposits rich in quartzite sandstones cropping in the studied area, but its upper member, about 200 may be considered as a facies deposited in shallow seas in m thick, with beds ranging from 30 cm to 12 m, is identified the margin part of Gondwana and peri-Gondwanan micro- in the Aldeaquemada area and described by Rey and Hidalgo continents in the stage of rifting and early drift of Avalonia (2004) and Lillo et al. (in press). Top beds of this member (Gutiérrez-Alonso et al., 2007). This area was a southern- display wavy bedding, cross-stratification and the trace fossil most part of Gondwana and was situated near the South Pole Cruziana. during the Early Ordovician (e.g., Cocks and Torsvik, 2002). The Pochico Formation, around 200 m-thick in the studied Although a general ichnological characterization of the area, is made up of alternating quartzites, quartz sandstones, Armorican Quartzite is lacking to date, trace fossils are an sandy shales, siltstones and mudstones. Stratal stacking al- important feature of this facies. They have been described lows three members to be distinguished (Tamain, 1972). Ac- in several sections and areas on the Iberian Peninsula (e.g., cording to Gutiérrez-Marco et al. (2013), the Pochico Forma- Delgado, 1886a, b; Bouyx, 1966; Baldwin, 1975, 1977a, b, c; tion probably corresponds to the Dapingian sequence sensu Crimes and Marcos, 1976; Kolb and Wolf, 1979; Pickerill et lato in the southern part of the Central-Iberian Zone in Spain, al., 1984; Romano, 1991; Neto de Carvalho, 2006; Sá et al., being in this case the Middle Ordovician in age (Bergström et 2011) and in France (Rouault, 1850; Lebesconte, 1883, 1886; al., 2009). The Lower Member (Pochico Alternations Mem- Durand 1984, 1985a, b; Fortey and Owens, 1999). ber) is around 60 m thick and features a series of quartzite In this paper, we describe a trace fossil assemblage in one beds alternating with finer sediments, showing wavy-bed- section of the Armorican Quartzite facies, just on the transi- ding (Fig. 2A), horizontal lamination (Fig. 2D), wave ripple tion of the Armorican Quartzite sensu stricto, and overlying cross-lamination and locally low angle cross-stratification heterolithic facies of the Pochico Formation in the Aldeaque- (Fig. 2E). The Middle Member (Yellowish Pochico Sand- mada section (Cimbarra section in Rey and Hidalgo, 2004), stone Member) contains about 100 m thick sandy shales with Central Iberian Zone (Fig. 1). Its palaeoenvironment is inter- wavy-bedding and locally hummocky cross-stratification. A preted in the Gondwanan and peri-Gondwanan context. Con- few horizons show distinct cracks (Fig. 2F). In the Middle sidering that the Pochico Formation is ichnologically almost Member, lingulid horizons have been recorded and related unexplored, a discussion of the more general ichnological to short catastrophic events (Emig and Gutiérrez-Marco, features of this facies based on the literature serves to sup- 1997). The Upper Member or Pochico Quartzite Intercala- port our interpretation. Collected trace fossils are housed in tions Member (50 m thick) is characterized by numerous the Department of Stratigraphy and Palaeontology, Faculty of quartzite beds intercalated with finer clastics, similar to the Sciences, University of Granada (label Aq). first member. Most of these rocks are characterized by the low degree of sediment reworking and primary structures are 2. Geological setting usually clearly visible. This study is focused on sedimentological and ichnologi- During the Early Ordovician, the Iberian Massif formed cal features at the transition between the Armorican Quartzite part of the northwest margin of Gondwana (e.g., Von Raumer Formation and the Pochico Formation, where a 29 m-thick et al., 2003). The studied area is located in the southernmost section was measured bed by bed (Fig. 3). These formations part of the Iberian Massif, in the Central Iberian Zone, ac- contact with a conformity showing gradual lithological tran- cording to a subdivision into different zones (Fig. 1A) based sition. According to Matas-González et al. (2009), the Lower on different stratigraphic-tectonic-metamorphic features Member of the Pochico Formation was deposited on a silici- (Julivert et al., 1972). The studied outcrop is located in the clastic shelf dominated by storms. Cascada de la Cimbarra, in the Sierra Morena Mountains Trace fossils were rarely mentioned from the Armorican (Fig. 1B), province of Jaen, 2.5 km south of Aldeaquemada Quartzite and the Pochico Formation (especially the lower Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 541

Fig. 1.- Geological setting. A, Iberian Peninsula and subdivisions of the Iberian Massif according to stratigraphic, tectonic and metamorphic features. The studied area is located in the southernmost part of the Central Iberian Zone. B, Detailed geological setting of the studied outcrop (GPS co-ordinates: N38°23.150′; W003°22.474′; ±9 m). C, Aldeaquemada section and illustrations of the lithological formations appearance in the field. Note location of the studied profile as a bar.

member) of the study area, which is covered by the Geologi- iana cf. lefevbrei, Didymaulichnus lyelli, Monocraterion isp., cal Map of Aldeaquemada (862, 1:50,000; a second edition Monomorphichnus isp., Bergaueria isp. and Isopodichnus still in press is unavailable, see Lillo et al., in press). Rey isp., are mentioned in the map explanations. and Hidalgo (2004) mention large and small Cruziana and Skolithos from the lower part of the Pochico Formation in 3. Systematic palaeontology the study region. In the surrounding areas, trace fossils have been described in the Pochico Formation, including Cruziana Ichnogenus Archaeonassa Fenton and Fenton, 1937a furcifera, C. goldfussi, C. rugosa, Rusophycus isp., Didy- cf. Archaeonassa isp. (Fig. 4A) maulichnus rouaulti, Arthrophycus cf. harlani and Daedalus Material: One loose slab in the field. halli (Pérez Regodón, 1966; Butenweg, 1968; Poupon, 1971; Description: Tamain, 1972). In nearby areas, covered by the surrounding Epichnial, shallow furrow, 2-3 mm wide, with narrow Geological Maps 838 (Santa Cruz de Mudela), 840 (Bienser- levees. Its course is slightly to strongly winding with occa- vida), and 787 (Alhambra), other ichnotaxa, such as Cruz- sional loops. The loops measure 15-30 mm across. 542 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555

Fig. 2.- Sedimentary structures from the Aldeaquemada section. A, Wavy ripples on the top of beds of quartzite. B-C, Heterolithic quartzite-siltstone deposit. D, Beds of quartzite with parallel lamination. E, Low angle cross-stratification in sandstone beds. F, Cracks in upper surface of beds.

Remarks: ton and Fenton, 1937a; Buckman, 1994; Stanley and Feld- The winding course with occasional loops resembles mann, 1998) or crustaceans (Yochelson and Fedonkin, 1997; Helminthoidichnites Fitch (Hofmann and Patel, 1989), which Mángano and Buatois, 2003). A. fossulata is larger and does however does not display levees, when preserved as a fur- not display loops as the described cf. Archaeonassa isp. row. Levees are typical of Archaeonassa fossulata Fenton and Fenton, 1937a, the type ichnospecies of Archaeonassa, Ichnogenus Catenichnus McCarthy, 1979 which is interpreted as a crawling trail of gastropods (Fen- Catenichnus isp. (Fig. 4B) Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 543

Material: About 10 specimens in the upper part of a quartz- ly 20 mm deep. The cylinders are thinly to thickly lined with itic sandstone bed observed in the field. mudstone or siltstone. Description: Remarks: U-shaped cylinder with divergent arms. The cylinder is Some of specimens of the type ichnospecies Catenichnus of uniform diameter, which ranges from 7 to 11 mm among contentus McCarthy, 1979 from the Permian of Australia, dis- specimens. The structure is 11-60 mm wide and approximate- play poorly developed spreite, which are absent in the studied

Fig. 3.- Profile of the Cascada de la Cimbarra outcrop with indication of sedimentary structures and ranges of selected trace fossils. 544 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 material. Trace fossils of this morphology, but without spre- Ichnogenus Cruziana ďOrbigny, 1842 ite, are also ascribed to Arenicolites, which however displays Cruziana furcifera ďOrbigny, 1842 (Fig. 5A-F) parallel arms (see Hofmann et al. 2011 for discussion). Cat- Material: Six specimens collected, with numerous occur- enichnus contentus can be interpreted as a domichnion pro- rences observed in the field. duced by a suspension feeder (McCarthy, 1979). It occurs in Description: moderate to high energy facies (Fillion and Pickerill, 1990). Straight to loosely meandering bilobate ridges of uniform The same interpretation may be applied to Catenichnus isp. width ranging from 30 to 130 mm. The lobes of the ridges are described here. semi-ellipsoidal in cross section and separated by a distinct V-shaped furrow. Their surface is densely covered by oblique Ichnogenus Cochlichnus Hitchcock, 1858 distinct ridges, which are 0.5-2 mm wide. The ridges meet Cochlichnus isp. (Fig. 7D) in the median furrow at an angle less than 30º, forming a Material: Two specimens observed in the field. V-shaped unidirectional pattern. In some specimens, narrow Description: lateral ridges are observed (Fig. 5C). An epichnial, horizontal, regularly sinuous ridge. The ridge Remarks: is 2 mm wide. The amplitude of the meanders attains 6-8 mm Delgado (1886) distinguished almost twenty ichnospe- and the meanders are 2 mm high. cies of Cruziana from the Lower Palaeozoic of Portugal, Remarks: yet Seilacher (1970) retained only C. furcifera, C. goldfussi Cochlichnus occurs in a great variety of marine and non- and C. rugosa, and considered the remaining ichnospecies marine environments. It is produced by many different in- to be taphonomic variations of these three ichnospecies. The vertebrates, including annelids and nematodes (see Fillion separation of Cruziana goldfussi (Rouault), distinguished and Pickerill, 1990, for review). Cochlichnus from non-ma- from C. furcifera in terms of its finer and more continuous rine settings have been referred to scavengers or predators scratch marks (see Fillion and Pickerill, 1990 for discussion), (Głuszek, 1995), an interpretation that can also be extended is problematic because of transitional specimens. Also, the to occurrences in marine settings. presence or absence of lateral ridges used to discern these two

Fig. 4.- A, cf. Archaeonassa isp., epichnial semirelief on medium bed of sandstone. B, Cat- enichnus isp. drawing on unfo- cused photograph of hyporelief on medium bed of sandstone. Cascada de la Cimbarra, Po- chico Formation (Lower/Mid- dle Ordovician). Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 545

Fig. 5.- A-F, Cruziana furcifera ďOrbigny, 1842. Hypichnia with convex semirelief on medium to thick beds of sandstones. D, C. furcifera (Cf), C. tenella (Ct) and cf. Monocraterion isp. (M). E, C. furcifera, cf. Monocraterion isp. (M). Cascada de la Cimbarra, Pochico Forma- tion (Lower/Middle Ordovician). 546 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 ichnotaxa, is problematic as they occur in the type material Remarks: of both ichnospecies (Durand, 1985a). Therefore, Mángano The transverse corrugations are characteristic features of and Buatois (2003) regarded C. furcifera, C. goldfussi and this subichnospecies. It is considered as a locomotion-feed- C. rugosa as subichnospecies of C. rugosa (respectively: C. ing burrow of trilobites (e.g., Seilacher, 1970, 2007). rugosa furcifera, C. rugosa goldfussi and C. rugosa rugosa). Specimen of Cruziana rugosa illustrated herein on Fig. 6 However, many other authors retain them at the ichnospecies show only short fragment of up and down probing tracemaker level (e.g., Aceñolaza and Milana, 2005; Neto de Carvalho, work. Therefore, the resulted hypichnia (Fig. 6A) are similar 2006) regarding that all the three ichnotaxa display distinc- to the rusophyciform of Rusophycus marginatus Bergström tive morphological features (e.g., Egenhoff et al., 2007). and Peel, 1988. Cruziana is interpreted as the feeding trace of trilobites and/or other arthropods such as aglaspids, limulids or phyllo- Cruziana tenella (Linnarsson, 1871) (Figs. 5D, 6C, 8A) pods, whereas C. rugosa is attributed exclusively to trilobites Material: Two collected slabs containing few specimens. A (e.g., Seilacher, 1970, 2007). few additional specimens observed in the field. Description: Cruziana imbricata Seilacher, 1970 (Fig. 8A) Hypichnial bilobate, straight or slightly winding ridges, Material: One slab containing two specimens. 2.5-8 mm wide. It displays faint, perpendicular striae in some Description: specimens, while other specimens are smooth. A short, bilobate, hypichnial ridge, 8-20 mm long, 4-19 Remarks: mm wide, 1-4 mm high. The lobes are covered by distinct, The perpendicular striae are most significant morphologi- uniformly thick (1-2 mm wide), gently curved regularly dis- cal features distinguishing this ichnospecies, even if some tributed scale-like ridges, which meet in the median furrow smooth forms occur in the same population of burrows. Pres- at an angle of about100º and form a V-shaped, unidirectional ence of perpendicular striae or smooth surface (like Didy- pattern in the median furrow. maulichnus isp.) on hypichnia depends on taphonomy. This is Remarks: well visible in much larger Cruziana furcifera from the study The trace fossil was originally described as Cruziana im- area, where preservation of bioglyphs deteriorates along the bricata Seilacher, 1970, which includes also forms that bilobate ridge up to their disappearance. Additionally, speci- should be ascribed to Rusophycus (for the later see also Sá et mens of C. tenella and part of specimens of Cruziana rouaulti al., 2011). Cruziana imbricata is common in the Arenigian (which is generally smooth) are of the same width; indeed, in association the Cruziana rugosa group (Seilacher, 1970). in some cases distinction between these two ichnospecies is problematic. Cruziana rouaulti Lebesconte, 1883 (Fig. 6C) Cruziana tenella is known from the Cambrian (see Sadlok, Material: One collected specimen and a few specimens ob- 2010 for review), but also from the Grebes Nest Point Forma- served in the field. tion (Arenigian) of Newfoundland, where it was described Description: under Cruziana stromnessi (Trewin, 1976). Cruziana tenella This is a hypichnial bilobate ridge bounded with side ridg- is commonly described under Isopodichnus, which is a loco- es. The lobes are smooth, semi-circular in cross section, and motion and feeding trace of phyllopod crustaceans in non- show a wide median furrow. The whole structure is 11-18 marine environments (Pollard, 1985). It is widely accepted mm wide. The side ridges are 1-3 mm wide. that Isopodichnus is a junior synonym of Cruziana, though Remarks: some researches retain this name (e.g., Seilacher, 2007). The This trace fossil was assigned to Didymaulichnus Young, taxonomic relation between C. tenella and Isopodichnus is 1972 (e.g., Crimes, 1970; Knaust, 2004), which mostly problematic (Jensen, 1997). In any case, C. tenella has a pri- smooth, bilobate ridge. However, many authors ascribed it to ority. It can be referred to the locomotion-feeding activity of Cruziana ďOrbigny (e.g., Neto de Carvalho, 2006; Seilacher, small arthropods, including phyllopods for the non-marine 2007). This is supported by the presence of scratches in well variants. preserved specimens (Egenhoff et al., 2007). The strongly developed side ridges suggest a carapace of an arthropod. Ichnogenus Didymaulichnus Young, 1972 Crimes (1970) considered the discussed trace fossil as a trace Didymaulichnus lyelli (Rouault, 1850) (Fig. 6D) of trilobites. Material: One slab containing mass occurrence specimens. A few single specimens in the field. Cruziana rugosa ďOrbigny, 1842 (Fig. 6A-B) Description: Material: A few specimens documented in the field. Hypichnial, straight to slightly winding, smooth bilobate Description: ridge, 7-10 mm wide, with a narrow V-shaped median fur- Hypichnial, bilobate ridge 90-100 mm wide, with trans- row, which is 1 mm wide. The ridge is bounded by thin, dis- verse corrugations, covered by oblique, fine, comb-like ridg- continuous bevels, about 1 mm thick. It occurs together with es. The preserved fragments of ridges are 150-200 mm long. Cruziana rouaulti in some beds. Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 547

Fig. 6.- A, Cruziana rugosa ďOrbigny, 1842. B, C. rugosa (Cr) and cf. Monocraterion isp. (M). C, Cruziana tenella (Linnarsson, 1871) (Ct), Cruziana rouaulti Lebesconte, 1883 (Cro), Gordia isp. (G) and Lockeia cf. siliquaria James, 1879 (L). D, Didymau- lichnus lyelli Rouault, 1850. E, ?Diplichnites isp. Hypichnial, concave semireliefs on medium beds of sandstone. Cascada de la Cimbarra, Pochico Formation (Lower/Middle Ordovician). 548 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555

Remarks: Remarks: Didymaulichnus is interpreted as a trail of gastropods The discs are a typical bedding plane expression of Lin- (Glaessner, 1969; Hakes, 1976) or trilobites (Crimes, 1970; gulichnus, which is a shaft, U-shaped when fully devel- Bradshaw, 1981). Didymaulichnus is a common facies-cross- oped, with the elliptical cross-section. The bevel can be an ing trace fossil in the Lower Palaeozoic (for a review see Fil- expression of a thick lining. Lingulichnus is interpreted as lion and Pickerill, 1990; Kumpulainen et al., 2006). D. lyelli a domichnion of lingulid brachiopods (Hakes, 1976; Zonn- is known from the Armorican Quartzite (Durand, 1985a). eveld and Pemberton, 2003; Zonneveld et al., 2007).

Ichnogenus Diplichnites Dawson, 1873 Ichnogenus Lockeia James, 1879 ?Diplichnites isp. (Fig. 6E) Lockeia cf. siliquaria James, 1879 (Fig. 6C) Material: One specimen collected. Material: Two collected slabs containing several speci- Description: mens. The trace fossil is composed of two parallel rows of hyp- Description: ichnial, irregular to more regular ridges, which are arranged Lockeia cf. siliquaria occurs as amygdaloidal mounds, obliquely to the main axis of the structure. Each row is 25-30 which are 3-4 mm wide and 7-8 mm long, up to 2-3 mm high, mm wide and separated by the median smooth part, about pointed on both sides, with a median longitudinal keel. 20 mm wide. The whole structure is about 60 mm wide. The Remarks: rows are composed of mostly straight ridges, which are 1-2 Stout forms of Lockeia have been ascribed to L. amy- mm wide, 3-5 mm apart. Some of them appear to be out- gdaloides (Seilacher, 1953), and narrow forms to L. siliquar- wardly bifid, but in others it is not evident due to poor preser- ia James, 1879. However, Seilacher and Seilacher (1994) and vation. In one row a wide V-shaped arrangement of the ridges Schlirf et al. (2001) held them to be morphological variants is also present. of L. siliquaria James, because they occur in the same beds Remarks: together with transitional forms between these two ichno- A bad state of preservation does not permit closer determi- species. This is the cubichnion produced mostly by bivalves nation. One can consider it even as an undertrack of Cruziana (Seilacher and Seilacher, 1994) in various environments, but or Rusophycus, but partial preservation of lower surface of mostly shallow-marine settings. the bed (lower part of Fig. 6E) excludes such a possibility. Diplichnites is interpreted as a locomotion trace of arthro- Lockeia isp. (Fig. 7D) pods, typical of Palaeozoic-early Mesozoic shallow-marine, Material: About 30 specimens in a loose slab observed in occasionally deeper-marine environments (Fillion and Pick- the field. erill, 1990). Description: Amygdaloidal or drop-shaped mounds on the lower surface Ichnogenus Gordia Emmons, 1844 of sandstone beds, which are 16-27 mm wide and 27-60 mm Gordia isp. (Fig. 6C) long, pointed on one side (drop-shaped) or both sides. Material: One collected specimen. Remarks: Description: Its larger size, occasional drop-shape and the absence of a Convex, hypichnial, subcylindrical ridge forming a loop. keel are the features differentiating it from Lockeia cf. sili- The ridge is about 3 mm wide and loop is about 20 mm wide. quaria. The ridge crosses Didymaulichnus rouaulti. Remarks: Ichnogenus Monocraterion Torell, 1870 Formation of loops is typical of Gordia Emmons, 1844, cf. Monocraterion isp. (Figs. 5D, E, 6B, 7A) which is a pascichnion formed by various organisms in dif- Material: Several slabs containing abundant specimens ob- ferent environments (e.g., Fillion and Pickerill, 1990; Geyer served in the field. and Uchman, 1995). The described form is similar to Gordia Description: marina Emmons, 1844, but fragmentary preservation does Vertical to subvertical, straight, simple shafts crossing not permit a closer determination. quartzitic sandstone bed, showing a steep conical upper part, filled with mudstone-siltstone. Only a part of the structure Ichnogenus Lingulichnus Hakes, 1976 limited to the 20 cm thick host sandstone bed was observed. ?Lingulichnus verticalis Hakes, 1976 (Fig. 7B) The conical part is up to 80 mm long and up to some 10 mm Material: Two specimens observed on a bedding plane of in diameter in the upper part. In horizontal section, the coni- a loose slab. cal part is manifest on the upper bedding plane as a circular Description: or oval disc-like structure, which is about 10 mm in diameter, Elliptical disc on a bedding surface, 15 mm wide and 22-29 with a centric or eccentric knob of various sizes and occasion- mm long, with an external bevel riming the disc. The bevel ally expressed concentric rings. The lower part is expressed varies in width from 1 to 3 mm. on the bedding plane as oval to circular knobs. Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 549

Fig. 7.- A, cf. Monocraterion isp. (arrowed), endichnia, full reliefs in medium bed of sandstone. B, ?Lingulichnus verticalis Hakes, 1976. C, Lockeia cf. siliquaria James, 1879. D, Lockeia isp. and Cochlichnus isp. (C). E, Planolites beverleyensis (Billings, 1862). F, Planolites isp. G, Planolites montanus Richter, 1937. H, Ptychoplasma excelsum Fenton and Fenton, 1937b. B, C, D, F-H, hypichnia, convex semireliefs on thin to medium beds of sandstones; E, endichnion in medium bed of sandstone. Cascada de la Cimbarra, Pochico Formation (Lower/Middle Ordovician). 550 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555

Fig. 8.- A, Cruziana imbricata Seilacher, 1970 (Ci) and Cruziana tenella (Linnarsson, 1871) (Ct); B, Rusophycus isp., hypichnia, convex semireliefs on thin beds of sandstones. C-D, epichnial bilobate ridges on rippled beds. Cascada de la Cimbarra, Pochico Formation (Lower/Middle Ordovician).

Remarks: occurs in various marine and non-marine facies, and is pro- Validity of Monocraterion as a separate ichnogenus, con- duced by vermiform invertebrates of many phyla, which are sidered by some authors as the same trace fossil as Skolithos interpreted as deposit-feeders that actively fill their burrows Haldeman (interpreted as erosionally truncated Monocrate- (e.g., Pemberton and Frey, 1982; Keighley and Pickerill, rion) is confirmed (see Fillion and Pickerill, 1990); howev- 1995). er, we follow the idea that it is better to separate these with funnel from these without funnel, if the erosional truncation Planolites montanus Richter, 1937 (Fig. 7G) is not evident. The type material displays some ridges run- Material: A few specimens documented in the field. ning from the funnel, which pose certain unsolved taxonomic Description: problems (Jensen, 1997). Therefore, the described material is Hypichnial, short, semi-cylindrical, smooth, straight to determined as cf. Monocraterion isp. Monocraterion sensu slightly curved ridges, 6-7 mm wide, up to 23 mm long. The lato is typical of shallow-marine, high-energy sandy facies ridges plunge into the bed. and is interpreted as a domichnion of suspension-feeders or Remarks: scavengers (e.g., Schlirf and Uchman, 2005). This ichnospecies is characterized by common change of orientation on short distances, and what is manifested by Ichnogenus Planolites Nicholson, 1873 short courses on bedding plains, while course of other ich- Planolites beverleyensis (Billings, 1862) (Fig. 7E) nospecies of Planolites are more stable (Pemberton and Frey, Material: A few specimens documented in the field. 1982). This trace fossil reflects reworking of mudstone-sand- Description: stone interface. Hypichnial or endichnial, horizontal to oblique, unbranched curved or straight, smooth cylindrical structure, 6-12 mm in Planolites isp. (Fig. 7F) diameter, without distinct lining. Material: A few specimens documented in the field. Remarks: Description: The diagnosis of P. beverleyensis “relatively large, smooth, Planolites isp. is a horizontal to subhorizontal, rarely ob- straight to gently curved or undulate Planolites” (Pemberton lique, unbranched gently curved, rarely straight, smooth cy- and Frey, 1982) fits the described material well. Planolites lindrical structure, without distinct lining. There are two dif- Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 551 ferent size classes: the smallest specimens are about 2 mm in Remarks: diameter and larger ones about 4 mm in diameter. A closer determination is impossible because of fragmen- Remarks: tary preservation. Gyrochorte comosa Heer, which is typical- The mostly horizontal course and the smaller size are the ly preserved as an epichnial bilobate ridge, displays oblique main differences from P. beverleyensis, whose diagnosis con- ribbing and is typically narrower (Gibert and Benner, 2002). tains the phrase “relatively large…” (Pemberton and Frey, 1982). 4. Discussion

Ichnogenus Ptychoplasma Fenton and Fenton, 1937b 4.1. Palaeoenvironmental aspects Ptychoplasma excelsum Fenton and Fenton, 1937b (Fig. 7H) Material: One collected specimen and a few observations The trace fossil assemblage is moderately diverse (13 ich- in the field. nogenera, 19 ichnospecies), dominated by pascichnia (Ar- Description: chaeonassa, Cruziana, Gordia, Planolites) and repichnia (Co- Hypichnial ridges 5-9 mm wide, with elongate, smooth chlichnus, Didymaulichnus, ?Diplichnites, Ptychoplasma), mounds, some of which separated by more even segments. the presence of domichnia (Catenichnus, Lingulichnus, cf. The mounds are amygdaloidal in cross section, 11-20 mm Monocraterion) and cubichnia (Lockeia, Rusophycus). This long, up to 9 mm high and only slightly wider than the even assemblage is typical of the Cruziana ichnofacies in general ridge. The overall course is winding; some segments inter- (e.g., Frey and Seilacher, 1980) and of the archetypal Cruz- sect. iana ichnofacies in particular, which in open shelf sediments Remarks: points to the lower shoreface-upper offshore, where deposit Ptychoplasma excelsum was known so far from the Carbon- feeding prevails (Pemberton et al., 2001). In the Lower Pal- iferous of USA (Fenton and Fenton, 1937b; Rindsberg, 1994). aeozoic sediments, a reversal of ichnofacies can occur, i.e., the The Arenigian occurrence extends its stratigraphic range. Pty- Cruziana ichnofacies may occur in tidal flat heterolithic sedi- choplasma is interpreted as the locomotion and feeding trace ments, while the Skolithos ichnofacies is present in subtidal of bivalves, and occurs in various marine and non-marine en- sand bars (Buatois and Mángano, 1999, 2004). Nevertheless, vironments (Uchman et al., 2011); however, P. excelsum is there are no signs of tidal environment. Instead, the presence limited so far to shallow-marine settings (Rindsberg, 1994). of hummocky cross stratification indicates storm influences, which is consistent with previous observations (Rey and Ichnogenus Rusophycus Hall, 1852 Hidalgo, 2004). The classic facies depth interpretation can Remarks: therefore be applied. Furthermore, in Portugal, the Armorican Rusophycus is a resting trace of arthropods, mostly trilo- Quartzite is interpreted as foreshore-upper offshore sediment bites in Palaeozoic (Osgood, 1970), considered by Seilacher (Neto de Carvalho, 2006). This does not necessarily apply to (1970) as Cruziana, but most authors keep these ichnogenera the Armorican Quartzite facies in other regions. For instance, separate (e.g., Fillion and Pickerill, 1990, for discussion). Cruziana-rich facies are referred to tidal flats in NW Spain (Crimes and Marcos, 1976) and in the Armorican Massif (Du- Rusophycus isp. (Fig. 8B) rand, 1984, 1985a, b; Dabard et al., 2007; Vidal et al., 2011). Material: One collected specimen and a few observations The presence of Cruziana, Rusophycus and other trace in the field. fossils attributed to trilobites would suggest normal salinity. Description: However, the common occurrence cracks in the upper part of An oval, bilobate hypichnion, 22 mm long, 23 mm wide, 7 the section (Fig. 3) might be referred to salinity changes, as mm high, which consists of two symmetrical lobes separated “syneresis” cracks (Burst, 1965). In this part of the section, by an indistinct median furrow. The surface of the lobes is the trace fossils are absent. Only in metre 20-21 of the section irregular. Incomplete ridges occur on the steep slope of one (Fig. 3) is Cruziana present together with the cracks. How- side. They display a wide V-shaped pattern. ever, the latest investigations show that cracks of such type Remarks: can be intrastratal cracks caused by shrinkage of sediments General shape of the discussed specimen corresponds containing microbial structures (Harzim et al., 2013). Never- somewhat with Rusophycus dispar Linnarsson, 1869, al- theless, the relation of the cracks to microbial structures is not though the bad state of preservation does not permit closer obvious in the investigated section. determination. The low degree of sediment reworking suggests a high rate of clastic sedimentation. The most abundant occurrences of Epichnial bilobate ridge (Fig. 8C-D) trace fossils are in mudstone-sandstone intercalations, where Material: Two specimens in the field. sandstone prevails. Such sediments are probably the most nu- Description: tritional, attracting deposit feeders, while the preservational Epichnial, smooth, bilobate, slightly curved ridges, with potential is high due to lithological heterogeneity, especially semi-circular lobes that are about 7 mm wide. on sandstone-mudstone interfaces. Most sandstone beds dis- 552 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 play well preserved primary sedimentary lamination. Not all In other hand, the distribution of trace fossils in the Ordo- sandstone-mudstone intercalations contain trace fossils (Fig. vician is also facies controlled (Mángano and Droser, 2004). 3). Total bioturbation is confined to thin horizons. This may Baltica, which during the Ordovician was closer to the Equa- be attributed to a high rate of sedimentation, when the time tor, is characterized by dominant condensed carbonate sedi- available for colonization (colonization window sensu Pol- mentation, with numerous discontinuity surfaces (Cocks and lard et al., 1993) of bedforms was insufficient. Torsvik, 2005). The Baltica facies are rich in skeletal fossils Generally, trace fossil are relatively uncommon in pure and relatively scarce in trace fossils (Ekdale and Bromley, quartzitic sandstones of the Armorican Quartzite facies (e.g., 2001, 2003; Dronov et al., 2002; Dronov and Mikuláš, 2010), Kolb and Wolf, 1979). Sandstones with some admixture of especially Cruziana, which is believed to be a palaeo-ichno- finer fractions yield characteristic trace fossils, e.g., Sko- zoogeographic marker. One can invoke an effect of antago- lithos and Daedalus, which are attributable to the Skolithos nism between suspension feeders and deposit feeders, i.e. ichnofacies, indicating a high-energy environment above the trophic group amensalism (Rhoads and Young, 1970), which fair-weather wave base. The associated heterolithic facies is also applicable to trace fossils (Bromley, 1996; Buatois and are characterized by abundant pascichnia, such as Cruziana, Mángano, 2011). It is an open question if the tropic group typical of the Cruziana ichnofacies. amensalism, observed generally in a scale of habitat, can be extrapolated to whole continents. Probably, the stronger role 4.2. Palaeogeographic background was played by the taphonomic filter, as preservation of trilobite trace fossils is highest in heterolithic siltstone-sandstone The Lower Ordovician and Lower/Middle Ordovician deposits (Crimes, 1975; Goldring, 1985). The calcareous, trace fossils of the Gondwana and peri-Gondwanan zone are commonly condensed sediments of Baltica are not suitable highly diverse. The Ordovician is an important time of biodi- for preservation of trilobite burrows. versification in shallow marine environments, which is also recorded in trace fossils (Mángano and Droser, 2004). So far, 5. Conclusions the highest ichnodiversity in the Ordovician (38 ichnogenera) comprises several formations of the Wabana and Bell Island The described trace fossils belong to the archetypal Cruz- groups in Newfoundland (Fillion and Pickerill, 1990). How- iana ichnofacies, indicating a lower shoreface-upper offshore ever, these formations differ from Armorican Quartzite facies zone. A high rate of sedimentation limited the colonization formations in that they are composed mostly of shales or het- window of bedforms, causing a generally low degree of bio- erolithic rocks, except for the Redmans Formation, made up turbation. of massive quartzite similar to the Armorican Quartzite. This The studied trace fossil assemblage has significant but quartzitic formation yields scarce trace fossils – only Cruz- not strict palaeogeographic implications in the Gondwana iana furcifera was described (Fillion and Pickerill, 1990). and peri-Gondwanan context. The trace fossil assemblages The distribution of some Lower Ordovician trace fossils of Cruziana ichnofacies in the Armorican Quartzite facies is controlled by different aspects, among others by palaeo- (margins of Gondwana) are characterized by common large geographical location. Foremost, these concerns trace fossils, Cruziana, in this sense differing from the Baltica setting. which morphology depends largely from anatomy of trace- Ichnofauna of Early Ordovician was palaeogeographically maker, such as Cruziana or Rusophycus. The Cruziana ru- controlled, although trilobite related ichnotaxa typical of gosa group is very common in the Iberian Peninsula, France, Gondwana can be found rarely in Baltica and Laurentia. The Wales, North Africa, southern Asia and South America, which differences between the ichnofauna of Gondwana and Bal- represents the northern margin of Gondwana (e.g., Cocks and tica may be influenced by the facies (clastics in Gondwana Torsvik, 2002). This group of trace fossils is generally absent and carbonates in Baltica), mostly owing to the preservation in Laurentia (continental part of North America and Green- potential of Cruziana, which is high in heterolithic clastic land) and Baltica (Eastern Europe and Scandinavia) (Seilach- sediments. er and Crimes, 1969). Nevertheless, the palaeogeographical restriction is not strict. The C. rugosa group and other trace Acknowledgements fossils, e.g., Trichophycus venosus, were reported from the Norwegian part of Baltica (Knaust, 2004) despite the fact that The paper benefited from comments and suggestions by Baltica during the Ordovician was separated from Gondwana Drs Gutiérrez-Marco (Instituto de Geociencias; CSIC, UCM) by the Tornquist Sea (e.g., Cocks and Torsvik, 2002). and one Anonymous Reviewer. A. U. and M. S. received Mixed Gondwanan-Baltic assemblages of trilobites, which additional support from Jagiellonian University. Research are Cruziana trace-makers, have also been reported from the by R.-T. was supported by Projects CGL2008-03007, and Cambrian of Poland (Żylińska, 2002). The possibility of pre- CGL2012-33281 (Secretaría de Estado de I+D+I, Spain), Ordovician paths of migration of ichnofaunas between Lau- Project RNM-3715 and Research Group RNM-178 (Junta rentia and Baltica palaeocontinents, based on Rusophycus, de Andalucía). The previous version of the paper benefitted was mentioned by Stachacz (2012). from critical review of Nicholas Minter (Portsmouth, UK). Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 553

References Cocks, L.R.M., Torsvik, T.H. (2005): Baltica from the late Precambrian to mid-Palaeozoic times: The gain and loss of a terrane’s identity. Earth- Aceñolaza, G.F., Milana, J.P. (2005): Remarkable Cruziana beds in the Science Reviews 72, 39-66. doi:10.1016/j.earscirev.2005.04.001 Lower Ordovician of the Cordillera Oriental, NW Argentina. Ameg- Crimes, T.P. (1970): Trilobite tracks and other trace fossils from the hiniana 42, 633-637. Upper Cambrian of North Wales. Geological Journal 7, 47-68. doi: Baldwin, C.T. (1975): The stratigraphy of the Cabos Series in the section 10.1002/gj.3350070104 between Cadavedo and Laurca, Province of Oviedo, N. W. Spain. Bre- Crimes, T.P. (1975): The production and preservation of trilobite rest- viora Geológica Astúrica 19, 4-9. ing and furrowing traces. Lethaia 8, 35-48. doi: 10.1111/j.1502- Baldwin, C.T. (1977a): Rusophycus morgati: An asaphid produced trace 3931.1975.tb00914.x fossil from the Cambro-Ordovician of Brittany and northwest Spain. Crimes, T.P., Marcos, A. (1976): Trilobite traces and the age of the Journal of Paleontology 51, 411-425. http://www.jstor.org/stable/ lowest part of the Ordovician reference section for NW Spain. i255830 Geological Magazine 113, 349-356. http://dx.doi.org/10.1017/ Baldwin, C.T. (1977b): Internal structures of trilobite trace fossils in- S0016756800047622 dicative of an open surface furrow origin. Palaeogeography, Pal- Dabard, M.P., Loi, A., Paris, F. (2007): Relationship between phospho- aeoclimatology, Palaeoecology 21, 273-284. doi: 10.1016/0031- genesis and sequence architecture: Sequence stratigraphy and bios- 0182(77)90039-6 tratigraphy in the Middle Ordovician of the Armorican Massif (NW Baldwin, C.T. (1977c): The stratigraphy and facies associations of trace France). Palaeogeography, Palaeoclimatology, Palaeoecology 248, fossils in some Cambrian and Ordovician rocks of north western Spain. 339-356. doi: 10.1016/j.palaeo.2006.12.011 In: Crimes, T.P., Harper, J.C. (eds.), Trace fossils 2, Geological Journal, ďOrbigny, A. (1842): Voyage dans l’Amérique méridionale (le Brésil, Special Issue 9, 9-40. la République orientale de l’Uruguay, la République Argentine, la Bergström, J., Peel, J.S. (1988): Lower Cambrian trace fossils from north- Patagonie, la République du Chili, la République de Bolivia, la Répu- ern Greenland. Rapport Grønlands geologisk Undersøgelse 137, 43-53. blique du Pérou) exécuté pedant les années 1826, 1827, 1829, 1830, Bergström, S.M., Chen, X., Gutiérrez-Marco, J.C., Dronov, A.V. 1831, 1832 et 1833, pt. 4 (Paléontologie). Pitois-Levrault (Paris), (2009): The new chronostratigraphic classification of the Ordovi- Levrault (Strasbourg). cian System and its relations to major regional series and stages and Dawson, J.W. (1873): Impressions of footprints of aquatic animals and δ13C chemostratigraphy. Lethaia 42, 97-107. doi: 10.1111/j.1502- imitative markings, on Carboniferous rocks. American Journal of 3931.2008.00136.x Science 5, 16-24. Billings, E. (1862): New species of fossils from different parts of the Delgado, J.F.N. (1886a): Terrains palézoiques du Portugal. Étude sur les Lower, Middle and Upper Silurian rocks of Canada. In: Palaeozoic Bilobites et autres fossiles des quartzites de la base du système Silu- Fossils, Volume I (1861–1865). Geological Survey of Canada, Daw- rique du Portugal. Académie Royale des Sciences, Lisbonne. son Brothers, Montreal, 96-168. Delgado, J.F.N. (1886b): Étude sur les Bilobites et autres fossiles des Bouyx, E. (1966): Répartition verticale des pistes bilobées dans l’Or- quarzites de la base du système Silurique du Portugal. Sections des dovicien inférieur de la provincie Ciudad Real (Espagne méridional). Travaux Géologiques de Portugal, Académie Royale des Sciences, Compte Rendu Sommaire des séances de la Société géologique de Lisbonne. France 1966 (1), 88-89. Dronov, A., Mikuláš, R. (2010): Paleozoic Ichnology of St. Petersburg Bradshaw, M. (1981): Paleoenvironmental interpretations and system- region. IV Workshop on Ichnotaxonomy. Excursion Guidebook. Rus- atic of Devonian trace fossils from the Taylor Group (Lower Beacon sian Academy of Science, Moscow. Transactions of the Geological Supergroup), Antarctica. New Zealand Journal of Geology and Geo- Institute 596, 1-70. physics 24, 615-652. doi:10.1080/00288306.1981.10421537 Dronov, A.V., Mikuláš, R., Logvinova, M. (2002): Trace fossils and Bromley, R.G. (1996): Trace Fossils. Biology, Taphonomy and Applica- ichnofabrics across the Volkhov depositional sequence (Ordovician, tions. Second Edition. Chapman and Hall, London, 361 p. Arenigian of St. Petersburg Region, Russia). Journal of the Czech Buatois, L.A., Mángano, M.G. (1999): Ichnofacies models in Early Geological Society 47, 133-144. Paleozoic tide-dominated quartzites: onshore-offshore gradients and Durand, J. (1984): Ichnocenoses du grès Armoricain (Ordovicien the classic Seilacherian paradigm. Acta Universitatis Carolinae 43, Inférieur du Massif Armoricain) dans leur contexte sédimentolo- 151-154. gique. Geobios, Memoir Special 8, 189-197. DOI : 10.1016/S0016- Buatois, L.A., Mángano, M.G. (2004): Terminal Proterozoic-Early 6995(84)80172-2 Cambrian ecosystems: ichnology of the Puncoviscana Formation, Durand, J. (1985a): Les traces fossiles paleobiologices de milieux: un northwest Argentina. In: Webby, B.D., Mángano, M.G., Buatois L.A. exemple dans l’Ordivicien Armoricain. Bulletin du Muséum national (eds), Trace Fossils in Evolutionary Palaeoecology, ed. Fossils and d’histoire naturelle. Section C, Sciences de la terre, paléontologie, Strata 51, 1-16. géologie, minéralogie C3, 215-227. Buatois, L.A., Mángano, M.G. (2011): Ichnology: Organisms-Substrate Durand, J. (1985b): Les Grès Armoricain. Sédimentologie-Traces fos- Interactions in Space and Time. Cambridge University Press, Cam- siles. Milieux de dépôt. Mémoires et Documents, Centre Armoricain bridge, 358 p. ďEtude Structurale des Socles, 3, 1-150. Buckman, J.O. (1994): Archaeonassa Fenton and Fenton 1937 reviewed. Egenhoff, S.O., Weber, B. Lehnert, O., Maletz, J. (2007): Biostrati- Ichnos 3, 185-192. doi:10.1080/10420949409386387 graphic precision of the Cruziana rugosa group: a study from the Burst, J.F. (1965): Subaqueously formed shrinkage cracks in clay. Jour- Ordovician succession of southern and central Bolivia. Geological nal of Sedimentary Research 35, 348-353. Magazine 144, 289-303. doi: 10.1017/S0016756807003093 Butenweg, P. (1968): Geologische Untersuchungen im Ostteil der Sierra Ekdale, A.A., Bromley, R.G. (2001): Bioerosional innovation for living Morena nordöstlich von La Carolina (Prov. Jaén, Spanien). Münster- in carbonate hardgrounds in the Early Ordovician of Sweden. Lethaia sche Forschungen zur Geologie und Paläontologie 6, 126 p. 34, 1-12. doi: 10.1080/002411601300068152 Cocks, L.R.M., Torsvik, T.H. (2002): Earth geography from 500 to 400 Ekdale, A.A., Bromley, R.G. (2003): Paleoethologic interpretation of million years ago: a faunal and palaeomagnetic review. Journal of complex Thalassinoides in shallow-marine limestones, Lower Or- the Geological Society, London 159, 631-644. doi: 10.1144/0016- dovician, southern Sweden. Palaeogeography, Palaeoclimatology, 764901-118 Palaeoecology 192, 221-227. doi: 10.1016/S0031-0182(02)00686-7 554 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555

Emig, C.C., Gutierrez Marco, J.C. (1997): Signification des Niveaux Hofmann, H.J., Patel, I.M. (1989): Trace fossils from the type „Etch- à lingulidés à la limite supérieure du Grès Armoricain (Ordovician, emian Series” (Lower Cambrian Ratcliffe Brook Formation), Saint Arenig, SW Europe). Geobios 30, 481-495. doi: 10.1016/S0016- John area, New Brunswick, Canada. Geological Magazine 126, 139- 6995(97)80116-7 157. doi: 10.1017/S0016756800006294 Emmons, E. (1844): The Taconic System: Based on observations in New- Hofmann, R., Goudemand, N., Wasmer, M., Bucher, H., Hautmann, York, Massachusetts, Maine, Vermont, and Rhode-Island. Caroll and M. (2011): New trace fossil evidence for an early recovery signal in Cook, Albany, 67 p. the aftermath of the end-Permian mass extinction. Palaeogeography, Fenton, C.L., Fenton, M.A. (1937a): Archaeonassa: Cambrian snail Palaeoclimatology, Palaeoecology 310, 216-226. doi: 10.1016/j.pal- trails and burrows. American Midland Naturalist 18, 454-458. aeo.2011.07.014 Fenton, C.L., Fenton, M.A. (1937b): Burrows and trails from Pennsyl- James, U.P. (1879): Description of new species of fossils and remarks on vanian rocks of Texas. American Midland Naturalist 18, 1079-1084. some others, from the Lower and Upper Silurian rocks of Ohio. The Fillion, D., Pickerill, R.K. (1990): Ichnology of the Upper Cambrian? Paleontologist 3, 17-24. to Lower Ordovician Bell Island and Wabana groups of Eastern New- Jensen, S. (1997): Trace fossils from the Lower Cambrian Mickwitzia foundland, Canada. Palaeontographica Canadiana 7, 1-83. sandstone, south-central Sweden. Fossils and Strata 42, 1-110. Fortey, R.A., Owens, R.M. (1999): Feeding habits in trilobites. Palaeon- Julivert, N., Fontboté, J.M., Ribeiro, A., Conde, L.E. (1972): Mapa tology 42, 429-465. doi: 10.1111/1475-4983.00080 tectónico de la Península Ibérica y Baleares, 1:1.000.000, Memoria Frey, R.W., Seilacher, A. (1980): Uniformity in marine invertebrate ich- Explicativa, Instituto Geológico y Minero de España. nology. Lethaia 13, 183-207. doi: 10.1111/j.1502-3931.1980.tb00632.x Keighley, D.G., Pickerill, R.K. (1995): The ichnotaxa Palaeophycus Geyer, G., Uchman, A. (1995): Ichnofossil assemblages from the Nama and Planolites: historical perspectives and recommendations. Ichnos Group (Neoproterozoic-Lower Cambrian) in Namibia and the Pro- 3, 301-309. doi:10.1080/10420949509386400 terozoic-Cambrian boundary problem revisited. Beringeria Special Knaust, D. (2004): Cambro-Ordovician trace fossils from the SW-Nor- Issue 2, 175-202. wegian Caledonides.Geological Journal 39, 1-24. doi: 10.1002/gj.941 Gibert, J.M. de, Benner, J.S. (2002): The trace fossil Gyrochorte: etholo- Kolb, S., Wolf, R. (1979): Distribution of Cruziana in the Lower Ordo- gy and paleoecology. Revista Española de Paleontología 17(1), 1-12. vician sequence of Celtiberia (NE Spain) with a revision of the Cruz- Glaessner, M.F. (1969): Trace fossils from the Precambrian and basal iana rugosa-group. Neues Jahrbuch für Geologie und Paläontologie Cambrian. Lethaia 2, 369-393. doi: 10.1111/j.1502-3931.1969. Monatshefte 1979, 457-474. tb01258.x Kumpulainen, R.A., Uchman, A., Woldehaimanot, B., Kreuser, T., Ghir- Głuszek, A. (1995): Invertebrate trace fossils in the continental deposits may, S. (2006): Trace fossil evidence from the Adigrat Sandstone for of an Upper Carboniferous coal–bearing succession, Upper Silesia, an Ordovician glaciation in Eritrea, NE Africa. Journal of African Poland. Studia Geologica Polonica 108, 171-202. Earth Sciences 45, 408-420. doi: 10.1016/j.jafrearsci.2006.03.011 Goldring, R. (1985): The formation of the trace fossil Cruziana. Geologi- Lebesconte, M. (1883): Présentation des oeuvres posthumes de Marie cal Magazine 122, 65-72. doi: 10.1017/S0016756800034099 Roualt, suivie d’une note sur les Cruziana et Rusophycus. Bulletin de Gutiérrez-Alonso, G., Fernández-Suárez, J., Gutiérrez-Marco, J.C., la Société géologique de France sér. 3, XI, 466-472. Corfu, F., Murphy, J.B., Suárez, M. (2007): U-Pb depositional age for Lebesconte, M. (1886): Constitution générale du massif breton compa- the upper Barrios Formation (Armorican quartzite facies) in the Can- rée à celle du Finistére. Bulletin Société Géologique de France sér. tabrian zone of Iberia: Implications for stratigraphic correlation and 3, 14, 776-811. paleogeography. In: Linnemann, U., Nance, R.D., Kraft, P., Zulauf, G. Lillo, F.J., López-Sopeña, F., Pieren, A., Hernández-Samaniego, A., (eds.), The evolution of the Rheic Ocean; from Avalonian-Cadomian Salazar, A., Gutiérrez-Marco, J.C., Sarmiento, G.N., Pardo-Alonso. active margin to Alleghenian-Variscan collision. Geological Society M.V., in press: Mapa y memoria explicativa de la hoja 863 (Aldeaque- of America, Special Papers 423, 287-296. mada) del Mapa Geológico 1:50.000. Instituto Geológico y Minero Gutiérrez-Marco, J.C., Robardet, M., Rábano, I., Sarmiento, G.N., Lan- de España. cha, M.Á.S.J., Araújo, P.H., Pindal. A.P.P. (2002): Ordovician. In: Linnarsson, J.G.O. (1869): On some fossils found in the Eophyton sand- Gibbons, W., Moreno, T. (eds.), Geology of Spain. The Geological stones at Lugnås in Sweden. Geological Magazine 6, 393-406. Society, Bath, 31-49. Linnarsson, J.G.O. (1871): Geognostiska och palaeontologiska iakt- Gutiérrez-Marco, J.C., Abréu Sá, A., Capdevila García-Bellido, D., tagelser öfver Eophytonsandstenen i Vestergötland. Kongliga Sven- Rábano, I. (2013). The extent of the Middle Ordovician Stage in ska Vetenscaps. Akademiens Handlingar 9, 1-19. peri-Gondwanan Europe and north Africa: stratigraphic record, bios- Mángano, M.G., Buatois, L.A. (2003): Trace fossils. In: Benedetto, J.L. tratigraphic tools and regional chronostratigraphy. GFF, 2013, doi: (Ed.), Ordovician Fossils of Argentina. Universidad Nacional de Cór- 10.1080/11035897.2013.865667 doba, Secretaría de Ciencia y Tecnología, 507-553. Hakes, W.G. (1976): Trace fossils and depositional environment of Mángano, M.G., Droser, M. (2004): The ichnologic record of the Or- four clastic units, Upper Pennsylvanian megacyclothems, northeast dovician radiation. In: Webby, B.D., Droser, M.L., Paris, F., Percival, Kansas. The University of Kansas, Paleontological Contributions 63, I.G. The Great Ordovician Biodiversification Event. Columbia Uni- 1-46. versity Press, New York, 369-379. Hall, J. (1852): Palaeontology of New-York. II. Containing Descriptions Matas-González, J., Leyva, F., Cabra, P., Granados, L.F., Gutiérrez- of the Organic Remains of the Lower Middle division of the New-York Marco, J.C., Rodríguez-González R.M. (2009): Mapa y memoria ex- System (Equivalent in Part to the Middle Silurian rock of Europe). plicativa de la hoja 864 (Venta de los Santos) del Mapa Geológico Geological Survey of New York, C. Van Benthuysen, Albany, New 1:50.000. Instituto Geológico y Minero de España. York, 362 p. McCarthy, B. (1979): Trace fossils from a Permian shoreface – fore- Harazim, D., Callow, R.H.T., McIlroy, D. (2013): Microbial mats impli- shore environment, Eastern Australia. Journal of Paleontology 53, cated in the generation of intrastratal shrinkage (‘syneresis’) cracks. 345-366. http://www.jstor.org/stable/1303876 Sedimentology 60, 1621-1638. doi: 10.1111/sed.12044 Neto de Carvalho, C. (2006): Roller coaster behavior in the Cruz- Hitchcock, E. (1858): Ichnology of New England: A Report on the Sand- iana rugosa group from Penha Garcia (Portugal): Implications stone of the Connecticut Valley, Especially its Fossil Footmarks. Nat- for the feeding program of trilobites. Ichnos 13, 255-265. doi: ural Sciences of America Reprint, Boston, 220 p. 10.1080/10420940600843740 Rodríguez-Tovar et al. / Journal of Iberian Geology 40 (3) 2014: 539-555 555

Nicholson, H.A. (1873): Contributions to the study of the errant anne- Seilacher, A. (1953): Studien zur Palichnologie II. Die fossilen lids of the older Palaeozoic rocks. Proceedings of the Royal Society Ruhespuren (Cubichnia). Neues Jahrbuch für Geologie und Paläon- London 21, 288-290. tologie, Abhandlungen 98, 87-124. Osgood, R.G., Jr. (1970): Trace fossils of the Cincinnati area. Palaeon- Seilacher, A. (1970): Cruziana stratigraphy of ‘‘non-fossiliferous’’ Pal- tographica Americana 6, 281-444. aeozoic sandstones. In Trace Fossils, ed. Crimes, T.P., and J.C. Harp- Pemberton, G.S., Frey, R.W. (1982): Trace fossil nomenclature and the er. Geological Journal, Special Issue 3, 447-476. Planolites – Palaeophycus dilemma. Journal of Paleontology 56, Seilacher, A. (2007): Trace Fossil Analysis. Springer, Heidelberg, 226 p. 843-881. http://www.jstor.org/stable/1304706 Seilacher, A., Crimes, T.P. (1969): „European” species of trilobite bur- Pemberton, G.S., Spila, M., Pulham, A.J., Saunders, T., MacEachern, rows in eastern Newfoundland. American Association of Petroleum J.A., Robbins, D., Sinclai, I.K. (2001): Ichnology & Sedimentology of Geologists, Memoir 12, 145-148. shallow to marginal marine systems: Ben Nevis & Avalon Reservoirs, Seilacher, A., Seilacher, E. (1994): Bivalvian trace fossils: a lesson from Jeanne D’Arc Basin. Geological Association of Canada, Short Course actuopaleontology. Courier Forschung Senckenberg 169, 5-15. Notes 15, 343 p. Stachacz, M. (2012): New finds of Rusophycus from the lower Cambri- Pérez Regodón, J. (1966): Nota sobre yacimientos fósiles encontrados an Ociesęki Sandstone Formation (Holy Cross Mountains, Poland). en Sierra Morena. Notas y Comunicaciones del Instituto Geológico y Geological Quarterly 56, 237-248. doi: 10.7306/gq.1018 Minero de España 91, 7-12. Stanley, T.M., Feldmann, R.M. (1998): Significance of nearshore trace- Pickerill, R., Romano, M., Meléndez, B. (1984): Arenig trace fossils fossil assemblages of the Cambro-Ordovician Deadwood Formation from the Salamanca area, western Spain. Geological Journal 19, 249- and Aladdin Sandstone, South Dakota. Annals of Carnegie Museum 269. doi: 10.1002/gj.3350190305 67(1), 1-51. Pollard, J.E. (1985): Isopodichnus, related arthropod trace fossils and Tamain, G. (1972): Recherches géologiques et minières en Sierra Morena notostracans from Triassic fluvial sediment.Transactions of the Royal orientale (Espagne). PhD. Thesis, Université Paris-Sud (Orsay). Tra- Society of Edinburgh, Earth Sciences 76, 273-285. doi: http://dx.doi. vaux du Laboratoire de Géologie Structurale et Appliquée 91, 1, 369 p. org/10.1017/S026359330001049X Torell, O. (1870): Petrificata Suecana Formationis Cambricae. Lunds Pollard, J.E., Goldring, R., Buck. S.G. (1993): Ichnofabrics contain- Universitet Arsskrift 6, 2, 1-14. ing Ophiomorpha: significance in shallow-water facies interpreta- Torsvik, T.H., Cocks, L.R.M. (2011): The Palaeozoic palaeogeography tion. Journal of the Geological Society of London 150, 149-164. doi: of central Gondwana. In: D.J.J. Van Hinsbergen, S.J.H. Buiter, T.H. 10.1144/gsjgs.150.1.0149 Torsvik, C. Gaina, S.J. Webb. (eds.), The Formation and Evolution Poupon, G. (1971): Contribution a l’étude de la région d’Aldeaquemada of Africa: A Synopsis of 3.8 Ga of Earth History, Geological Society (Jaén, Espagne). Msc. Thesis, Université Paris-Sud (Orsay): 60 p. London Special Publications 357, 137-166. Rey, J., Hidalgo, M.C. (2004): Siliciclastic sedimentation and sequence Trewin, N.H. (1976): Isopodichnus in a trace fossil assemblage from the stratigraphic evolution on a storm-dominated shelf: the Lower Ordo- Old Red Sandstone. Lethaia 9, 27-39. doi: 10.1111/j.1502-3931.1976. vician of the Central Iberian Zone (NE Jaén, Spain). Sedimentary Ge- tb00947.x ology 164, 89-104. doi: 10.1016/j.sedgeo.2003.08.004 Uchman, A., Mikuláš, R., Rindsberg. A.K. (2011): Mollusc trace fossils Rhoads, D.C., Young, D.K. (1970): The influence of deposit feeding or- Ptychoplasma Fenton and Fenton, 1937 and Oravaichnium Plička and ganisms on sediment stability and community trophic structure. Jour- Uhrová, 1990: their type material and ichnospecies. Geobios 44, 387- nal of Marine Research 28, 150-178. 397. doi: 10.1016/j.geobios.2010.08.001 Richter, R. (1937): Marken und Spuren aus allen Zeiten. I–II. Sencken- Vidal, M., Loi, A., Dabard, M.P., Botquelen, A. (2011): A Palaeozoic bergiana 19, 150-169. open shelf benthic assemblage in a protected marine environment. Rindsberg, A.K. (1994): Ichnology of the Upper Mississippian Hartselle Palaeogeography, Palaeoclimatology, Palaeoecology 306, 27-40. Sandstone of Alabama, with notes on other Carboniferous formations. doi: 10.1016/j.palaeo.2011.03.025 Geological Survey of Alabama, Bulletin 158, 1-107. Von Raumer, J.F., Stampfi, G.M., Bussy, F. (2003): Gondwana-derived Romano, M. (1991): Lower to middle Ordovician trace fossils from the microcontinents: the constituents of the Variscan and Alpine collision- Central Iberian Zone of Portugal and Spain. In: C.R. Barnes, S.H. al orogens. Tectonophysics 365, 7-22. doi: http://dx.doi.org/10.1016/ Williams (eds.), Advances in Ordovician geology, ed. Geological S0040-1951(03)00015-5 Survey of Canada 90-9, 191-204. Yochelson, E.L., Fedonkin, M.A. (1997): The type specimens (Middle Rouault, M. (1850): Note préliminaire sur une nouvelle formation dé- Cambrian) of the trace fossil Archaeonassa Fenton and Fenton. Cana- couverte dans la terrain silurien inférieur de la Bretagne. Bulletin de dian Journal of Earth Sciences 34, 1210-1219. doi: 10.1139/e17-097 la Société Géologique de France, série 2, 7, 724-744. Young, F.G. (1972): Early Cambrian and older trace fossils from the Sá, A.A., Gutiérrez-Marco, J.C., Piçarra, J.M., García-Bellido, D.C., southern Cordillera of Canada. Canadian Journal of Earth Sciences Vaz, N., Aceñolaza, G.F. (2011): Ordovician vs. «Cambrian» ichno- 9, 1-17. doi: 10.1139/e72-001 fossils in the Armorican Quartzite of Central Portugal. In: Gutiérrez- Zonneveld, J.P., Pemberton, S.G. (2003): Ichnotaxonomy and behav- Marco, J.C., Rábano, I., García-Bellido, D. (eds.), Ordovician of the ioral implications of lingulide-derived trace fossils from the Lower World, Cuadernos del Museo Geominero 14, 483-492. and Middle Triassic of Western Canada. Ichnos 10, 25-39. doi: Sadlok, G. (2010): Trace fossil Cruziana tenella from the Furongian 10.1080/10420940390238249 (Upper Cambrian) deposits of Poland. Acta Geologica Polonica 60 Zonneveld, J.P., Beatty, T.W., Pemberton S.G. (2007): Lingulide brachi- (3), 349-355. opods and the trace fossil Lingulichnus from the Triassic of western Schlirf, M., Uchman, A. (2005): Revision of the ichnogenus Sabellarifex Canada: Implications for faunal recovery after the end-Permian mass Richter, 1921 and its relationship to Skolithos Haldeman, 1840 and extinction. Palaios 22, 74-97. doi: 10.2110/palo.2005.p05-103r Polykladichnus Fürsich, 1981. Journal of Systematic Palaeontology Żylińska, A. (2002): Stratigraphic and biogeographic significance of 3(2), 115-131. doi: 10.1017/S1477201905001550 Late Cambrian trilobites from Łysogóry (Holy Cross Mountains, cen- Schlirf, M., Uchman, A., Kümmel, M. (2001): Upper Triassic (Keu- tral Poland). Acta Geologica Polonica 52, 217-238. per) non-marine trace fossils from the Haßberge area (Franconia, south-eastern Germany). Paläontologische Zeitschrift 75, 71-96. doi: 10.1007/BF03022599